Some time ago, we brought you the story of Shownice Boiled Salted Duck Eggs. The strange color of these eggs proved overwhelming to onlookers, but the flavor was reasonably respectable. After completing this assignment, it was only natural that we should progress to the next level in peculiar poultry products.
Unlike boiled salted duck eggs, preserved duck eggs aren’t found in the refrigerator section. They sit happily on the store shelves without need of any special treatment. Even the package helpfully reassures that these eggs can and should be kept at room temperature. Also unlike boiled salted duck eggs, preserved duck eggs aren’t cooked. That’s right, these are raw eggs, sitting right next to the cans of creamed corn.
Fear not, however, because these eggs have been around long enough to prove their worth as a fashion and fallow foodstuff. In addition to the rather sterile-sounding moniker we’ve already learned, preserved duck eggs are also known as “century eggs”, “thousand-year-old eggs”, and “millennium eggs”. In Thai, these delicious delicacies are called ไข่เยี่ยวม้า (khai yiao ma).
The traditional method of preserving duck eggs involves quicklime, salt, wood ash, and tea. Modern chemistry has improved the process, which is now performed with sodium carbonate, calcium hydroxide, and salt. Regardless of which method is used, the preserved duck egg undergoes a tremendous transformation. The white of the egg turns to a brown translucent gel, and the yolk becomes a creamy greenish-gray mass with an odor of ammonia. Once the change is complete, these eggs can keep for months with no refrigeration.
Upon removing the shell, one is first greeted with a speckled skin that belies the egg’s true appearance. Underneath this thin layer is the dark-brown (but also disturbingly translucent) “white”. Slicing into the peeled egg reveals the custard-like yolk in all of its olive-gray glory. It is at this point that the aforementioned aroma of ammonia is released.
Preserved duck eggs are certainly an acquired taste, but with a little practice it seems that it could be possible to enjoy these polychromatic poultry products from time to time, regardless of what you might choose to call them. And speaking of names, there is one name we haven’t yet explained. Khai yiao ma is what these eggs are called in Thailand, and it has to do with their forceful fragrance (and fortunately not their preparation procedure). Khai means “egg”; that’s simple enough. Ma means “horse”, which is a bit odd since these are duck eggs. And finally, yiao means…urine. That’s right: “horse urine eggs”.